They dip. They swoop. They spin through the air with grace. Hummingbirds are vibrant aerial acrobats, and the UCSC Arboretum will showcase their majesty this weekend at this year’s edition of the Hummingbird Days.

Each spring, Allen’s hummingbirds return to the central coast after spending the chilly winter roosting in the warmer climates of Southern California and Mexico. Once they arrive, the plucky, red-breasted travelers compete for territory occupied by the green and magenta Anna’s hummingbirds, which live in Santa Cruz year round.

“This time of year, the Allen’s come in. Even though they’re a little smaller, but they end up chasing away the Anna’s to some extent to other parts of the Arboretum,” says Stephen McCabe, the Arboretum’s curator of succulents and director of development and research.

“Some of our shrubs are 50 feet wide, so one hummingbird can’t defend an entire bush,” he continues. Between 20-50 birds can cluster around a single flowered shrub.

The event will run on Saturday and Sunday. Tours around the gardens will occur every half hour and will guide visitors through the center’s collection of flora from across the world.

“The hummingbirds concentrate most heavily around the grevilleas from Australia,” McCabe says. “These are flowers pollinated by larger birds in Australia, and so they’ve co-evolved to have larger amounts of nectar. They work really well for us.”

California native plants are great hummingbird magnets too, but to attract the hovering pollinators throughout the year, a “green thumb” needs a succession of flora.

“Our native plants tend to have shorter blooming seasons, so you’ll want manzanitas, then gooseberries, then columbines and sage, and then California fuchsias in the fall, and then hopefully the manzanitas start coming back in,” McCabe says.

Love Dive

One spectacle on display will be the aerial courtship of Allen’s hummingbirds. A male begins by swooping through the air over a shrub. Suddenly, like a rock flung from a slingshot, the male will zoom thirty feet in the air, before dive-bombing back towards the earth. The hummingbird pulls up at the last possible moment, flailing and waggling his tail feathers to make his signature screech.

“This is a territorial display, but it may also impress the females. There’s a lot of competition,” McCabe says.

“We also may see some of the Rufous hummingbirds that come from Mexico that come through here this time of year and then head up to Alaska.”

Arts and crafts will be available for kids, along with a new exhibit this year, “The Arboretum After Dark”. Mike Bolte, a wildlife photographer and astrophysics professor at the Lick Observatory, will present rare shots of animals that stalk the Arboretum at night, including coyotes, bobcats and mountain lions.

Plenty of chatter will focus on hummingbirds too. Bird photographer Larry Selman will dole out tips on building an outdoor studio for taking pictures of the flittering mini-fowl. Ten-minute mini-lectures will teach visitors how to identify different species, while McCabe will lead a session on the hummingbirds of Ecuador.

The UCSC Arborertum Hummingbird Days will run from 10-4 on Saturday and Sunday, March 1st and 2nd. To learn more go to their website, arboretum.ucsc.edu. Admission is $5 for adults, and $2 for children. Food will be available for purchase thanks to Global Village Café and A Little Morr Café.